It's no secret that Houston enjoyed the biggest charity season in history last year, with at least 21 charitable fundraisers from January through May of 2012 raising $1 million or more each — notable among them the Disco Legends bash, hosted by Sue and Lester Smith, which produced an unprecedented $32 million haul for the Texas Children's Cancer Center.

The Atlas of Giving's figures indicate that, in all, the city brought in a total of $11.23 billion in philanthropic dollars in 2012, representing 34.5 percent of the total given in Texas. That represents an increase of 11 percent over the $10.1 billion gifted the previous year in Houston, an increase significantly higher than the national average of 6.7 percent.

But don't expect these numbers to keep rising, says The Atlas, a Dallas-based company that measures nationwide charitable donations.

The company anticipates that 2013 will see the lowest giving growth rate in 50 years, as low as "1.6 percent nationwide due to expected declines in stock market returns and the 2 percent payroll tax hike.

However, Houston is known for bucking the trends — and this season is already off to an auspicious philanthropic start, with $1.2 million raised at the American Heart Association's Heart Ball, a $2 million gift committed to Houston Grand Opera and the $800,000-mark reached more than once.